Pyroxene-ideal
Thompson R M, Downs R T
American Mineralogist 89 (2004) 614-628
Model pyroxenes II: Structural variation as a function of tetrahedral rotation
model sodium vanadium px
with O3-O3-O3 angle = 173.0 and model oxygen radius = 1.300
_database_code_amcsd 0003500
9.712 8.992 5.192 90 109.7 90 C2/c
atom     x      y      z
V        0  11/12    1/4
Na       0    .25    1/4
Si   .3081   1/12  .2779
O1   .1339   1/12  .1679
O2   .3661    .25  .3321
O3   .3661  .0088  .0558